Summary White Sturgeon, Acipenser transmontanus (WS), are distributed throughout three major river basins on the West Coast of North America: the Sacramento‐San Joaquin, Columbia, and Fraser River drainages. Considered the largest North American freshwater fish, some WS use estuarine habitat and make limited marine movements between river basins. Some populations are listed by the United States or Canada as threatened or endangered (upper Columbia River above Grand Coulee Dam; Kootenai River; lower, middle and, upper Fraser River and Nechako River), while others do not warrant federal listing at this time (Sacramento‐San Joaquin Rivers; Columbia River below Grand Coulee Dam; Snake River). Threats that impact WS throughout the species’ range include fishing effects and habitat alteration and degradation. Several populations suffer from recruitment limitations or collapse due to high early life mortality associated with these threats. Efforts to preserve WS populations include annual monitoring, harvest restrictions, habitat restoration, and conservation aquaculture. This paper provides a review of current knowledge on WS life history, ecology, physiology, behavior, and genetics and presents the status of WS in each drainage. Ongoing management and conservation efforts and additional research needs are identified to address present and future risks to the species.

One of the practical problems with quantifying the amount of energy used by fish implanted with electromyogram (EMG) radio transmitters is that the signals emitted by the transmitters provide only a relative index of activity unless they are calibrated to the swimming speed of the fish. Ideally, calibration would be conducted for each fish before it is released, but this is often not possible. Consequently, calibration curves derived from more than one fish are used to interpret EMG signals from individuals that have not been calibrated. We tested the validity of this approach by comparing EMG data within three groups of three wild juvenile white sturgeon Acipenser transmontanus implanted with the same EMG radio transmitter. We also tested an additional six fish that were implanted with separate EMG transmitters. Within each group, a single EMG radio transmitter usually did not produce similar results in different fish. Grouping EMG signals among fish produced less accurate results than having individual EMG-swim speed relationships for each fish. It is unknown whether these differences resulted from different swimming performances among individual fish or from inconsistencies in the placement or function of the EMG transmitters. In either case, our results suggest that caution should be used when applying calibration curves from one group of fish to another group of uncalibrated fish.

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The issue of deep hooking is of concern in white sturgeon, Acipenser transmontanus Richardson, fisheries because nearly all anglers use bait with a stationary presentation on the river bottom to catch them, and bait fishing is often associated with higher instances of deep hooking and hooking mortality. Deep hooking rates, landing success and catch rates were investigated for anglers bait fishing for white sturgeon using circle and J hooks with inline and offset alignments fished with both active and passive hook‐setting methods. Anglers hooked 578 white sturgeon and landed 508 fish, ranging in size from 60 to 316 cm total length (mean = 137 cm). Deep hooking rates averaged 0.6% and did not differ between hook types, hook alignments or hook‐setting methods. Landing success (the proportion of hooked sturgeon that were successfully landed) and catch rates were also equivalent between hook types, hook alignments and hook‐setting methods; landing success averaged 88% and catch rates averaged 0.27 fish/hr. Results of this study indicate that deep hooking is rare when angling for white sturgeon using standard bait‐fishing gear regardless of hook‐setting method or whether circle or J hooks were used; regulations restricting hook type in sturgeon bait fisheries are therefore unwarranted.